There are two ways in which one can make headers using Ionic framework.
<div class="bar bar-header bar-dark">
<h1 class="title">Title</h1>
</div>
And
<header-bar title="'Title'" type="bar-dark">
</header-bar>
Links in Documentation : For first : http://ionicframework.com/docs/components/ For second : http://ionicframework.com/docs/angularjs/views/header/
What is the difference between them?